Dihydroxyphenoxy-aryl monoazo compounds



United States l atent (mice 3,303,183 DH-IYDROXYPHENDXY-ARYL MONOAZO COMPOUNDS Milton Green, Newton Center, Mass, assignor to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware No Drawing. Filed May 12, 1966, Ser. No. 549,486 3 Claims. (Cl. 260162) This application is a continuation-in-part of my copending application Serial No. 316,498, filed October 16, 1963, now abandoned, which is in turn a continuationin-part of my application Serial No. 680,403, filed August 26, 1957, now abandoned.

This invention relates to photography and more particularly to novel chemical compounds for use in products, compositions and processes for the development of photosensitive silver halide elements.

A principal object of this invention is to provide novel chemical compounds.

Another object is to provide novel syntheses for preparing the novel compounds of this invention.

Another object of the present invention is to provide novel processes and compositions for the development of silver halide emulsions, in which colored developing agents are used to develop a latent image.

Another object is to provide novel processes and compositions for the development of silver halide emulsions, in which the novel developing agent is capable of developing a latent image and imparting a reversed or positive colored image of said latent image to a superposed imagereceiving material.

A further object is to provide novel products, processes and compositions suitable for use in preparing monochromatic and multichromatic photographic images.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products and compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description.

The novel photographic developing agents employed in this invention possess the properties of both a dye and a developing agent; thus they may be referred to as dye developers. The nature of these dye developers will be described hereinafter.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of an exposed silver halide emulsion, whereby a positive dye image may be imparted to another element, herein referred to as an image-carrying or image-receiving element.

US. Patent No. 2,983,606, issued May 9, 1961, to Howard G. Rogers, discloses diffusion transfer processes wherein a photographic negative material, such as a photographic element comprising an exposed silver halide emulsion, is developed in the presence of a dye developer to impart to an image-receiving layer a reversed or positive dye image of the developed image by permeating into said emulsion layer a suitable liquid processing composition and bringing said emulsion layer into superposed relationship with an appropriate image-receiving layer.

It is an object of this invention to provide additional dye developers suitable for use in such processes.

B 31303,,l83 Patented Feb. 7, 1967 In carrying out the process of this invention, a photosensitive elernent containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example, by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, on an imagereceiving element. In a preferred embodiment, the photosensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the exposed silver halide emulsion is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developer silver, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It also may be due, in part, to a tanning effect on the emulsion by the oxidized developing agent. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer. Under certain circumstances, the layer of the liquid processing composition may be utilized as the image-receiving layer. The image-receiving layer receives a depthwise diffusion, from the emulsion, of unoxidized dye developer, without appreciably disturbing the imagewise distribution thereof, to provide a reversed or positive, colored image of the developer image. The image-receiving element may contain agents adapted to mordant or otherwise fix the diifused, unoxidized dye developer. If the color of the diffused dye developer is affected by changes in the pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. Imbibition periods of approximately one minute have been found to give good results, but this contact period may be adjusted where necessary to compensate for variations in temperature or other conditions. The desired positive image is revealed by stripping the image-receiving element from the photosensitive element at the end of the imbibition period.

The dye developers of this invention may be utilized in the photosensitive element, for example, in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving element when in superposed relationship therewith. Placing the dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any light-filtering action by the colored dye developer. In this preferred embodiment, the layer of dye developer may be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Similar concentrations may be used if the dye developer is utilized as a component of the liquid processing composition. In an especially useful mode of dispersing the dye developers in the photosensitive elements, the dye developer is dissolved in a Water-immiscible solvent and then dispersed in a gelatin coating solution.

The liquid processing composition above referred to comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate, and may contain the dye developer. In some instances, it may contain a minor amount of a conventional developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting the film-forming material of the type which, when said composition is spread and dried, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials or thickening agents whose ability to increase viscosity is substantially unaffected when left in alkaline solution for a long period of time may also be used.

The novel class of compounds of the present invention may be represented by the formula:

wherein Ar is an aryl nucleus, e.g., a benzene or naphthalene nucleus; each Z is an alkyl radical, such as methyl or ethyl, or a halogen such as chlorine; m is or 1, n is 0, 1 or 2, Y is an orthoor para-dihydroxyphenyl radical and alkyl and halogen substituted derivatives thereof; and X is the radical of an azo dye coupler linked to said N=N group and completing said azo dye.

In a preferred embodiment, the aryl nucleus is a henzene nucleus, in is 0 and Y is a p-dihydroxyphenyl radical. Such compounds may be represented by the formula: (13) OH Zn OI-I wherein Z, n and X have the same meaning as above.

As illustrations of suitable azo coupling components or couplers from which X may be derived, mention may be made of phenols and aromatic amines having a free position ortho or para to the hydroxyl or amino group, e.g., phenol, anilines, naphthols, anthrols, naphthylamines, etc.; heterocyclic aromatic compounds containing hydroxyl or amino groups, such as pyrazolones or pyrroles; aliphatic or alicyclic activated methylene couplers, i.e., compounds having an aliphatic or alicyclic methylene group activated by two adjacent keto, aldehyde, ester or nitrile groups, which may be the same or different, or a keto, aldehyde, ester or nitrile group in combination with an amide group, e.g., 1,3-diketones or fi-ketonic acid arylamides; etc., and substituted derivatives thereof. Examples of groups which may be present in such substituted derivatives include alkyl, sulfo, alkoxy, aryl, aryloxy, amino, keto, alkylamino, arylamino, hydroxyl, cyano, alkylamido arylamido, carbalkoxy, carboxamido, sulfonamido, etc.

As used herein with reference to X, the expression radical of a phenolic coupler is intended to refer to hydroxyphenyl, hydroxynaphthyl, hydroxyanthryl, etc. radicals, and substituted derivatives thereof; the expression radical of an aromatic amino coupler is intended to refer to aminophenyl, aminonaphthyl, etc. radicals, and substituted derivatives thereof; and the expressions radical of a heterocyclic aromatic coupler, radical of an aliphatic activated methylene coupler and radical of an alicyclic activated methylene coupler are to be similarly construed.

The novel compounds of the present invention may be prepared by diazotizing a compound of the formula:

(C) Zm n wherein Y is the protected derivative of the orthoand para-dihydroxyphenyl radical, preferably the acylated derivative thereof, and Z, n and Ar have the same meaning as above, and coupling the diazotized compound (C) into the desired coupling component providing X.

The compounds of Formula C may be prepared according to the procedure disclosed in US. Patent No. 3,061,- 434, issued October 30, 1962, to Milton Green and Warren E. Solodar.

The preferred compound within the group represented by Formula C is 1,5-diacetoxy-2-(p-aminophenoxy)-benzene The coupling is generally performed at a pH which is preferably not greater than about 9. The hydroxy groups of Y are protected during diazotization and coupling, as by the use of a bis-acetoxy derivative as mentioned above.

By the use of two moles of the diazonium salt to each mole of the coupling component, one may couple twice into certain of the coupling components which provide the residue X as, for example, phenols and aromatic amines such as 1,6-dihydroxynaphthalene and 1,5-diaminonaphthalene. Such coupling may give rise to a mixture, and it is contemplated to use such mixtures of monoand bis-azo dye developers.

Where the coupling component is a phenolic coupler, and particularly a naphthol, it has been found that cou pling ortho to the hydroxyl group gives a dye developer of superior color properties. It has also been found that such ortho-coupled dye developers exhibit essentially no pH sensitivity over a fairly wide range on either side of neutral.

As examples of suitable dye developers within the scope of this invention, mention may be made of the o H, 2-(p-[2,5"-dihydroxyphenoxy]-phenylazo)-4-methoxyl-naphthol 1-phenyl-3-methyl-4-(p- [2",5"-dihydroxyphenoxy] phenylaZo)-5-pyrazo1one As examples of additional coupling components which may be used to provide X, mention may be made of:

4-benzyl-1-naphthol 4-methyll -naphthol 4-methoxy-a-naphthylamine 4-acetamido-at-naphthylamine Phenol Aniline 1,5 -n aphthalenediamine l-hydroxyanthracene l-hydroxy-2-naphthanilide Diketohydrindene Malononitrile Acetoacetanilide 5 The following examples of the preparation of dye developers within the scope of this invention by coupling compounds within Formula C are given for the purposes of illustration only.

Example 1 5.7 gm. (0.19 mole) of 1,5-diacetoxy-2-(p-aminophenoxy)benzene was dissolved in 20 cc. of hydrochloric acid and diazotized with 1.4 gm. of sodium nitrite in 20 cc. of water at about 5 C. The resulting solution was added, with constant stirring, to a solution of 3 gm. (0.0173 mole) of 4-methoxy-1-naphthol in 100 cc. of acetone and 5 cc. of pyridine. Sodium bicarbonate solution (5 gum. in 200 cc. of water) was added to give a pH of approximately 8.0. The reaction mixture was stirred for two hours, then filtered. The resulting gum was transferred to a round bottom flask and hydrolyzed by heating for 15 minutes on a steam bath, in a solution of 5.6 gm. of potassium hydroxide in 100 cc. of water under nitrogen. The solution was cooled, filtered rapidly into a mixture of 50 cc. 3 N hydrochloric acid and ice. The resulting magenta solid was then filtered, washed with Water and dried in a desiccator over P After recrystallization from benzene and being dried under a vacuum, the product, 2-(p-[2", 5" dihydroxyphenoxy]-phenylazo)-4-methoxy-l-naphthol, melted at 187-189 C. and showed the following analySlS for C23H18N2O5.

Calculated: C, 68.8; H, 4.5; N, 7.0. Found: C, 68.7; H, 4.4; N, 6.9.

Example 2 1.8 gm. (0.006 mole) of p-aminophenoxyhydroquinone- 0,0-diacetate was dissolved in 25 cc. of water and 1.4 cc. of hydrochloric acid and diazotized with 0.006 mole of sodium nitrite in 5 cc. of water at about 5 C. The resulting solution Was added, with constant stirring, to a solution of 0.006 mole of 1-phenyl-3-methyl-5-pyrazolone in 50 cc. of acetone and cc. of pyridine. 45 cc. of a saturated sodium bicarbonate solution was added to give a pH of approximately 8.0. After half an hour, 50 cc. of water was added and the reaction mixture stirred for two hours, then filtered. The precipitate was washed with water and purified by dissolving it in methyl cellosolve and reprecipitating with Water. The acetyl groups were removed by hydrolysis in vacuo by heating for a few minutes on a steam bath, in a solution of 3 gm. of potassium hydroxide, 50 cc. of alcohol and 10 cc. of water. Precipitation with hydrochloric acid gave 1.8 gm. of the desired 1 phenyl 3-methyl-4-(p-[2",5-dihydroxyphenoxy] phenylazo) S-pyrazolone, After recrystallization from Xylene, 0.9 gm. was obtained, MP. 2289 C. The spectral absorption curve showed a A at 408 mg in acetone, e=24, 500.

It will be understood by those skilled in the art that other dye developers Within the scope of this invention may be prepared by substituting other couplers for those used in the above examples and/ or other diazo components, in accordance with well-known practices.

The following examples of the utilization of dye developers within the scope of this invention are given for purposes of illustration only.

Example 3 A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 3% of a 2 (p-[2",5-dihydroxyphenoxy]-phenylazo)-4-methoxyl-naphthol in a 4% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. The photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 4.5 1-pheny1-3-pyrazolidone 0.2 Sodium hydroxide 1.5 Potassium bromide 0.2

between said photosensitive element and an image-receiving element, as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose-coated *baryta paper which has been coated with a solution comprising 10% Nylon Type F8 (trade name of E. I. du Pont de Nemours and Co., Wilmington, Delaware, for N-methoxymethyl polyhexamethylene adipamide) in aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a magenta positive dye image of the photographed subject.

Example 4 A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 3% of 1 phenyl-3-methyl-4(p [2",5 dihydroxyphenoxy]- phenylazo)-5-pyrazolone in a 4% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. The photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 4.5 l-phenyl-3-pyrazolidone 0.2 Sodium hydroxide 1.5 Potassium bromide 0.2

between said photosensitive element and an image-receiving element, as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose-coated baryta paper which has been coated with a solution comprising 10% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a yellow positive dye image of the photographed subject.

The dye developers of this invention are also useful in integral multilayer photosensitive elements for use in multicolor dilfusion transfer processes. As an example of such photosensitive elements, mention may be made of the photosensitive elements disclosed and claimed in the copending US. application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13, 1956, wherein at least two selectively sensitized photosensitive strata are superposed on a single support and are processed, simultaneously and without separation, with a single common image-receiving element. A suitable arrangement of this type comprises a support carry ing a red-sensitive silver halide emulsion stratum, a greensensitive silver halide emulsion stratum and a bluesensitive silver halide emulsion stratum, said emulsions having associated therewith, respectively, a cyan dye developer, a magenta dye developer and a yellow dye developer. In one of the preferred embodiments of photosensitive elements of this type, the dye developers are disposed in separate alkali-permeable layers behind the photosensitive silver halide emulsion stratum with which they are associated.

The photosensitive elements within the scope of this invention may be used in roll film units which contain a plurality of photosensitive frames. The photosensitive elements of this invention are especially useful in composite roll film intended for use in a Polaroid Land Camera or a similar camera structure such, for example, as the camera forming the subject matter of US. Patent No. 2,435,717, issued to Edwin H. Land on February 10, 1948. In general, such composite roll films comprise a photosensitive roll, a roll of image-receiving material and a plurality of pods containing an aqueous alkaline processing solution. The rolls and pods are so associated with each other that, upon processing, the photosensitive element may be superposed on the imagereceiving element and the pods may be ruptured to spread the aqueous alkaline processing solution between the 7 superposed elements. The nature and construction of the pods used in such units are well known to the art. See, for example, U.S. Patents Nos. 2,543,181 and 2,634,886, issued to Edwin H. Land.

It will be noted that the liquid processing composition may contain one or more auxiliary or accelerating silver halide developing agents, such as p-rnethylaminophenol (Metol); 2-4-diaminophenol (Amidol); benzylaminophenol; hydroquinone; a substituted hydroquinone such as toluhydroquinone, phenylhydroquinone, or 4-methylphenylhydroquinone; or a 3-pyrazolidone such as l-phenyl-3-pyrazolidone. These silver halide developing agents are substantially colorless, at least in their unoxidized form. It is possible that some of the dye developer oxidized in exposed areas may be oxidized by an energy transfer reaction with oxidized auxiliary developing agent.

In addition, development may be efiected in the presence of an onium compound, particularly a quaternary ammonium compound, in accordance with the processes disclosed and claimed in U.S. Patent No. 3,173,786, issued March 16, 1965, to Milton Green and Howard G. Rogers.

The dye developers of this invention may be used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers to obtain black and white, monochromatic or toned prints or negatives. By way of example, a developer composition suitable for such use may comprise an aqueous solution of approximately 12% of the dye developer, 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline washing medium or other medium in which the unreacted dye developer is soluble. The expression toned is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver.

It should be noted that the dye developers of this medium are self-sufficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction between a color former or coupler and the oxidized developing agent, as well as so-called auto-coupling processes in which color is obtained by a reaction of the oxidized developing agent with unoxidized developing agent.

It will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of image-receiving elements and. adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to impart the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in U.S. Patent No. 2,647,049 to Edwin H. Land.

As examples of useful image-receiving materials, mention may be made of nylon, e.g., N-methoxymethyl polyhexamethylene adipamide, polyvinyl alcohol, and gelatin, particularly polyvinyl alcohol or gelatin containing a dye mordant such as poly-4-vinylpyridine. The image-receiving element also may contain a development restrainer, e.g., 1-phenyl-5-mercaptotetrazole, as disclosed in the copending application of Howard G. Rogers and Harriet W. Lutes, Serial No. 50,849, filed August 22, 1960.

The dye developers herein set forth are also useful in the formation of colored images in accordance with the photographic products and processes described and claimed in U.S. Patent No. 2,968,554, issued to Edwin H. Land on January 17, 1961.

The novel compounds herein disclosed are also suitable for use as dye for textile fibres, such as nylon.

In the preceding portions of the specification the expression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black.

Since certain changes may be made in the above products, compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A compound of the formula:

[--O-ArN=N-X wherein Ar is an aryl nucleus selected from the group consisting of benzene and naphthalene nuclei; each Z is selected from the group consisting of chlorine and lower alkyl groups; In is in integer from O to 1, inclusive; )1 is an integer from O to 2, inclusive; Y is selected from the group consisting of ortho-dihydroxyphenyl and para-dihydroxyphenyl; and X is the radical of an azo dye coupler linked to said N=N group.

2. 2 (p [2",5 dihydroxyphenoxy]-phenylazo)-4- methoxy-l-naphthol.

3. 1 phenyl 3 methyl-4-(p-[2,5-dihydroxyphenoxy] -phenylazo -5-pyrazolone.

No references cited.

CHARLES B. PARKER, Primary Examiner.

FLOYD D. HIGEL, Assistant Examiner. 

1. A COMPOUND OF THE FORMULA 